Pollination And Fertilisation

Plants reproduce sexually through pollination and fertilisation. They are the two most common and natural methods of childbirth. This procedure, which happens in all bisexual flowers, involves both the male and female reproductive components (anther and stigma). As a result, the reproductive organs of all flowering plants are referred to as flowers.

Pollination

It is the biological process by which pollen grains are transmitted from the male reproductive organ of a flower to its female reproductive organ. In this operation, pollen grains containing male genetic material are extracted from the anther and delivered to the stigma of a flower. During pollination, pollen grains are transferred between the anther and the stigma by several vectors such as wind, birds, honeybees, moths, and butterflies.

Pollination is classified into two categories, each of which is dependent on pollen grain distribution. Pollination occurs in two ways: self-pollination and cross-pollination. Christian Sprengeld, a German physicist, discovered it in the 18th century.

1. Self-Pollinating Plants

Pollen is carried from the anthers of a flower to the stigma of the same bloom, resulting in self-pollination. This type of pollination is commonly used by hermaphrodite or dioecious plants, which have both male and female sexual components on the same flower.

In self-pollinating plants, there is less need for external stimuli to promote pollination. Wind and other tiny insects that visit the bloom regularly are required for the survival of these plants. Self-pollinating flowers have anthers and stigma that are of equal lengths to enable pollen movement.

1. Pollination via Cross-Pollination

In this type of pollination, pollen is transferred from one flower’s anthers to the stigma of another flower. In this circumstance, the two flowers are genetically distinct from one another. The existence of another agent to transfer pollen is always required for cross-pollination to occur. Birds, animals, water, wind, and insects pollinate plants.

During fertilisation, female and male gametes combine to form a diploid zygote. After the carpel has been pollinated, something happens. The entire process of fertilisation occurs within the zygote for it to develop into a seed, and flowers, as angiosperm reproductive structures play an important part.

Fertilisation

During fertilisation, pollinators such as birds, honey bees, butterflies, flower beetles, and other insects carry male gametes to female reproductive organs, resulting in an embryo in a seed. In plants, there are three methods of fertilisation. The pollen tube enters the ovule in several ways, which allows them to be classified. The three types of fertilisation are chalazogamy, porogamy, and mesogamy.

Fertilisation Methods

The entry of the pollen tube into the ovule is used to categorise the fertilisation process into three stages.

Porogamy

This is the most common type of fertilisation in all angiosperms or blooming plants. In this technique of fertilisation, the pollen tube enters the ovule via the micropyle.

Chalazogamy

All Casuarina plant species use this form of fertilisation. In this case, the pollen tube penetrates the ovule via the pollen tube.

Mesogany

Mesogamy is a form of fertilisation used by all Cucurbit plants, including pumpkin, ridge gourds, bitter gourds, and other gourd species. In this technique of fertilisation, the pollen tube enters the ovule through the centre or integuments of the ovule.

Double Fertilisation 

Double fertilisation is a method of fertilisation that involves the fusion of a female gametophyte with two male gametes. In this procedure, one sperm cell fuses with the egg-producing zygote, while the other fuses with the two polar nuclei to generate endosperm. Every angiosperm plant undergoes a two-fertilisation cycle.

Difference Between Pollination And Fertilisation

Pollination and fertilisation have a lot of distinctions. Let’s take a look at a couple of them in more detail.

Conclusion 

We conclude that It is an element of flowering plants’ sexual reproduction process, which results in seeds that will grow into new plants. Flowers are flowering plant structures that contain all of the specialised elements required for sexual reproduction.